Patch "fbdev: controlfb: Add missing modes to fix out of bounds access" has been added to the 4.4-stable tree

Patch "fbdev: controlfb: Add missing modes to fix out of bounds access" has been added to the 4.4-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    fbdev: controlfb: Add missing modes to fix out of bounds access

to the 4.4-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     fbdev-controlfb-add-missing-modes-to-fix-out-of-bounds-access.patch
and it can be found in the queue-4.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From foo@baz Mon Dec 18 14:47:43 CET 2017
From: Geert Uytterhoeven <geert@linux-m68k.org>
Date: Thu, 9 Nov 2017 18:09:33 +0100
Subject: fbdev: controlfb: Add missing modes to fix out of bounds access

From: Geert Uytterhoeven <geert@linux-m68k.org>


[ Upstream commit ac831a379d34109451b3c41a44a20ee10ecb615f ]

Dan's static analysis says:

    drivers/video/fbdev/controlfb.c:560 control_setup()
    error: buffer overflow 'control_mac_modes' 20 <= 21

Indeed, control_mac_modes[] has only 20 elements, while VMODE_MAX is 22,
which may lead to an out of bounds read when parsing vmode commandline
options.

The bug was introduced in v2.4.5.6, when 2 new modes were added to
macmodes.h, but control_mac_modes[] wasn't updated:

https://kernel.opensuse.org/cgit/kernel/diff/include/video/macmodes.h?h=v2.5.2&id=29f279c764808560eaceb88fef36cbc35c529aad

Augment control_mac_modes[] with the two new video modes to fix this.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/video/fbdev/controlfb.h |    2 ++
 1 file changed, 2 insertions(+)

--- a/drivers/video/fbdev/controlfb.h
+++ b/drivers/video/fbdev/controlfb.h
@@ -141,5 +141,7 @@ static struct max_cmodes control_mac_mod
 	{{ 1, 2}},	/* 1152x870, 75Hz */
 	{{ 0, 1}},	/* 1280x960, 75Hz */
 	{{ 0, 1}},	/* 1280x1024, 75Hz */
+	{{ 1, 2}},	/* 1152x768, 60Hz */
+	{{ 0, 1}},	/* 1600x1024, 60Hz */
 };
 


Patches currently in stable-queue which might be from geert@linux-m68k.org are

queue-4.4/fbdev-controlfb-add-missing-modes-to-fix-out-of-bounds-access.patch